Package org.uma.jmetal.util.measure.impl

Class CountingMeasure

java.lang.Object

org.uma.jmetal.util.naming.impl.SimpleDescribedEntity

org.uma.jmetal.util.measure.impl.SimpleMeasure<Long>

org.uma.jmetal.util.measure.impl.SimplePushMeasure<Long>

org.uma.jmetal.util.measure.impl.CountingMeasure

All Implemented Interfaces:

Serializable, Measure<Long>, PullMeasure<Long>, PushMeasure<Long>, DescribedEntity

public class CountingMeasure
extends SimplePushMeasure<Long>
implements PullMeasure<Long>, PushMeasure<Long>

A CountingMeasure provides a simple way to evaluate a number of occurrences. For instance, it can be used to count how many solutions have been generated within an algorithm, how many evaluations have been computed, how many rounds have been run, etc. If these occurrences are provided by some PushMeasures, you can use link(PushMeasure) to register the CountingMeasure to these PushMeasures. Otherwise, use increment() when the CountingMeasure need to count one more occurrence. In order to get the count, one can access it immediately through get() or when it is updated by registering a listener with SimplePushMeasure.register(MeasureListener).

Author:

Matthieu Vergne

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
CountingMeasure()	Create a CountingMeasure starting from zero.
CountingMeasure(long initialCount)	Create a CountingMeasure which starts at a given value.
CountingMeasure(String name, String description)	Create a CountingMeasure starting from zero.
CountingMeasure(String name, String description, long initialCount)	Create a CountingMeasure which starts at a given value.

Method Summary

Modifier and Type	Method	Description
protected void	finalize()
Long	get()
void	increment()	Add 1 to the current count and push its value to all the registered observers.
void	increment(long amount)	Increment the current count in a given amount.
<T> void	link(PushMeasure<T> measure)	If this CountingMeasure is used to count the number of time a PushMeasure notifies its observers, you can use this method to link them.
void	reset()	Restart the counter to zero.
void	reset(long value)	Restart the counter to a given value.
<T> void	unlink(PushMeasure<T> measure)	If you have linked a PushMeasure through link(PushMeasure), you can discard the link by using this method.

Methods inherited from class org.uma.jmetal.util.measure.impl.SimplePushMeasure

push, register, unregister

Methods inherited from class org.uma.jmetal.util.naming.impl.SimpleDescribedEntity

description, name, setDescription, setName, toString

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.uma.jmetal.util.naming.DescribedEntity

description, name

Methods inherited from interface org.uma.jmetal.util.measure.PushMeasure

register, unregister

Constructor Details

CountingMeasure

public CountingMeasure(String name,
 String description,
 long initialCount)

Create a CountingMeasure which starts at a given value. The next value to be pushed to the registered observers will be this value + 1.

Parameters:

name - the name of the measure

description - the description of the measure

initialCount - the value to start from

CountingMeasure

public CountingMeasure(String name,
 String description)

Create a CountingMeasure starting from zero. The registered observers will receive their first notification when it will increment to 1.

Parameters:

name - the name of the measure

description - the description of the measure

CountingMeasure

public CountingMeasure(long initialCount)

Create a CountingMeasure which starts at a given value. The next value to be pushed to the registered observers will be this value + 1. A default name and description are used.

Parameters:

initialCount - the value to start from

CountingMeasure

public CountingMeasure()

Create a CountingMeasure starting from zero. The registered observers will receive their first notification when it will increment to 1. A default name and description are used.

Method Details

increment

public void increment()

Add 1 to the current count and push its value to all the registered observers.

increment

public void increment(long amount)

Increment the current count in a given amount. If the amount is zero, no change occurs, thus no notification is sent.

Parameters:

amount - the amount to add

get

public Long get()

Specified by:

get in interface PullMeasure<Long>

Returns:

the current amount of occurrences counted

link

public <T> void link(PushMeasure<T> measure)

If this CountingMeasure is used to count the number of time a PushMeasure notifies its observers, you can use this method to link them. The CountingMeasure will automatically register a MeasureListener on the PushMeasure such that, every time the PushMeasure send a notification, increment() is called. You can link several PushMeasures at the same time, but each of their notifications will increment the counter, leading to summing their notifications. When a PushMeasure should not be considered anymore, use unlink(PushMeasure) to remove the link.

Parameters:

measure - the PushMeasure to link

unlink

public <T> void unlink(PushMeasure<T> measure)

If you have linked a PushMeasure through link(PushMeasure), you can discard the link by using this method.

Parameters:

measure - the PushMeasure to unlink

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

reset

public void reset()

Restart the counter to zero. Generate a notification if the value was not zero.

reset

public void reset(long value)

Restart the counter to a given value. Generate a notification if the value was different.

Parameters:

value - the value to restart from